In 1857, after decades of legislative compromises, slave rebellions, and sectional squabbles, the United States stood poised on a knife’s edge. That year, the Supreme Court ruled in the notorious Dred Scott case that black people were not, and could never become, citizens, and that the national government lacked the authority to ban slavery in federal territories. Abolitionists and pro-slavery groups were waging a violent struggle over slavery in Kansas. And the Republican Party, founded and supported in part by anti-slavery activists, had just run its first official candidate for the presidency in 1856 and was preparing to challenge the Democrats’ federal power and—many Democrats feared—the institution of slavery itself.

It was at this fraught national moment that a group of New Englanders met at the Parker House in Boston to found The Atlantic. Though all of them were staunch opponents of slavery, they were also concerned that the hyper-partisanship of the era limited the exchange of ideas. In the magazine’s mission statement, published in the first issue in November 1857, the founders vowed, “The Atlantic will be the organ of no party or clique,” but would work to advance the “American idea” and “rank itself with that body of men which is in favor of Freedom, National Progress, and Honor, whether public or private.”

Over the following decade, as the country descended into civil war, faced the loss of Abraham Lincoln, and began the project of Reconstruction, The Atlantic put its founding principles to the test, covering the Civil War era with an overt and consistent abolitionist bent but also presenting a variety of perspectives on the contentious period.

The impending national conflict made no appearance in the magazine’s first issue, but abolitionist reformer Edmund Quincy faced it head on in the second. In “Where Will It End?” he issued an emphatic critique of slavery, denigrating the South for its moral and cultural failings and calling on Northerners to make a forceful stand for freedom.

Three years later, in October 1860, founding editor James Russell Lowell penned and published a ringing endorsement for Abraham Lincoln’s presidential candidacy in “The Election in November.” Though he hailed Lincoln as a “statesman” and praised him for his “ability” and “integrity,” Lowell’s expression of support was contextual rather than personal, rooted in a fierce, and clearly voiced, opposition to slavery.

Lowell returned to the pages of The Atlantic mere months later, after Confederate soldiers started the war by firing on Union forces at Fort Sumter, to detail the opening salvos of the conflict and decry the Confederate Rebellion in “The Pickens-and-Stealin’s Rebellion.” He framed the young Civil War in the same moral terms as he had the election in November, asserting: “We cannot think that the war we are entering on can end without some radical change in the system of African slavery.”

Ralph Waldo Emerson, one of the magazine’s founders, lent his own voice to the abolitionist cause in April 1862’s “American Civilization.” From the time of his presidential campaign, President Lincoln had prioritized national unity and called only for the containment, rather than the end, of slavery in the United States. But in a lecture at the Smithsonian Institution, in conversations with Lincoln himself, and, finally, in the pages of The Atlantic, Emerson argued, like Lowell, that slavery was central to the war, and asserted that emancipation was both a moral imperative and the only means of ending the conflict once and for all.

Less than six months later, on September 22, 1862, Lincoln declared in the aftermath of the Battle of Antietam:

On the first day of January, in the year of our Lord one thousand eight hundred and sixty-three, all persons held as slaves within any State, or designated part of a State, the people whereof shall then be in rebellion against the United States, shall be then, thenceforth, and forever free.

In “The President's Proclamation,” published in our November 1862 issue, Emerson applauded the pronouncement. Emancipation, he reiterated, was the war’s real moral purpose, and the proclamation would assure that “the lives of our heroes have not been sacrificed in vain.”

William Parker offered a more personal narrative of emancipation in “The Freedman’s Story,” published in two parts in 1866. Beginning with his birth into slavery in Maryland, Parker recalled his life in bondage and his eventual escape to a tenuous freedom in Pennsylvania, where a confrontation with a slaveholder erupted into the violent Christiana Riot of 1851.

The Atlantic also published a number of firsthand accounts of the war itself. In 1864 and 1865, Thomas Wentworth Higginson reported back from the front in the three-part “Leaves From an Officer's Journal,” in which he described his experience serving as the colonel of the country’s first federally authorized black regiment.

A decade later, George Cary Eggleston shared his own wartime experience in “A Rebel’s Recollections.” The story, serialized across seven issues of the magazine, introduced a new perspective to The Atlantic: that of a Confederate soldier. Eggleston, who belonged to a family of plantation-owning Virginians, instructed “the reader” that in order to understand the other side of the conflict, he “must make of himself, for the time at least, a Confederate. He must put himself in the place of the Southerners and look at some things through their eyes.”

Meanwhile, as Parker, Higginson, and Eggleston remembered their past experiences and other writers mourned the loss of Lincoln, Frederick Douglass was looking forward. In December 1866’s “Reconstruction” and the next month’s “An Appeal to Congress for Impartial Suffrage,” Douglass entreated the federal legislature to grant black Americans the right to vote. In contrast to Lowell’s and Emerson’s earlier framing of the Civil War as a clear moral struggle over the ultimate fate of slavery, Douglass warned that neither victory nor emancipation assured real freedom.

“This evil principle again seeks admission into our body politic,” he wrote. “It comes now in shape of a denial of political rights to four million loyal colored people. The South does not now ask for slavery. It only asks for a large degraded caste, which shall have no political rights.”

Three years later, Congress ratified the Fifteenth Amendment, granting all citizens unrestricted franchise. But in 1877, a decade after Douglass’s warning, Reconstruction came to an abrupt end when President Rutherford B. Hayes withdrew the last federal troops from the South, and, as The Atlantic marked its 20th anniversary, the Jim Crow era began.